EBay is calling on the federal government to legislate an end to the Canada Post contract dispute, warning that quick action is needed to ensure retailers don’t lose out on Black Friday and Cyber Monday sales.

The manager of the online sales giant’s Canadian and Latin American divisions says continued rotating strikes at Canada Post will result in significant losses for small and medium-sized businesses across the country.

While those businesses have adapted as best they can to the strikes that began Oct. 22, Andrea Stairs says in a letter to Prime Minister Justin Trudeau that the adjustments retailers have made so far to avoid delivery disruptions are unsustainable.

Meanwhile, Canada Post says it is now facing an unprecedented backlog of shipments, largely as a result of strikes at its major sorting plants in Vancouver and particularly Toronto.

A spokesman for the Crown corporation says that, as of this morning, there were more than 260 trailers filled with parcels waiting to be unloaded at its Gateway processing plant in Toronto — and that number is expected to rise quickly.

The prime minister warned last week that his government would look at all options to end the labour dispute if there is no significant progress in Canada Post’s contract talks with the Canadian Union of Postal Workers.